Puppies certainly mature much faster than us humans do. One moment, you have a small, rambunctious puppy, and the next, you could have a big adult dog lounging on the sofa. The rate that dogs grow and mature differs by their breed or anticipated adult size.
When will my puppy stop growing?
When your puppy will stop growing depends on whether they are a large-breed dog or a small-breed dog.
Large-breed dogs
When you have a large-breed dog, it’s common to wonder, “Just how big will my large-breed
puppy get?” Most large-breed dogs will reach their adult size between 12 and 18 months of age, though some breeds, such as mastiffs, may continue to grow until they’re around 2 years old.
Small-breed dogs
Small-breed dogs usually reach their adult size between 6 and 12 months of age. Really small dogs like Chihuahuas are more likely to reach their adult size toward the lower end of the range.
When is my puppy considered an adult dog?
You may notice that a lot of dog foods consider puppyhood to last from birth to 12 months of age, but this does not capture the variability that occurs due to breed.
There is no precise cutoff for when puppies are considered adult dogs, as it varies by the dog’s size. The end of the puppy phase is often considered to be when the dog’s rapid growth phase ends. For some really small dogs, this can be around 6 to 8 months of age. For medium dogs, it’s usually around a year. Your large- or giant-breed dogs can become adults closer to 18 to 24 months.
Your VCA care team will be able to give you a better estimate for when your older puppy will become an adult (if they haven’t already!).
View our chart to get an idea of how old your dog is in human years!
